|Name of place|Number of counties|Principal county|Lower zip code|
|---|---|---|---|
|Yager Junction|1|Humboldt County||
|Yale|1|Riverside County|92544|
|Yankee Hill|1|Butte County|95965|
|Yankee Hill|1|Tuolumne County||
|Yankee Jims|1|Placer County|95713|
|Yarmouth|1|San Joaquin County||
|Yellowjacket|1|Tehama County||
|Yerba Buena Island|1|San Francisco County||
|Yermo|1|San Bernardino County|92398|
|Yettem|1|Tulare County|93670|
|Ygnacio Valley|1|Contra Costa County|94598|
|Yokohl|1|Tulare County||
|Yolano|1|Solano County|95620|
|Yolo|1|Yolo County|95697|
|Yontocket|1|Del Norte County||
|Yorba|1|Los Angeles County|91767|
|Yorba Linda|1|Orange County|92686|
|York|1|Los Angeles County|90050|
|Yorkville|1|Mendocino County|95494|
|Yosemite Forks|1|Madera County||
|Yosemite Junction|1|Tuolumne County|95389|
|Yosemite Lakes|1|Madera County||
|Yosemite Lakes Park|1|Madera County||
|Yosemite Lodge|1|Mariposa County|95389|
|Yosemite National Park|3|Madera County|95389|
|Yosemite National Park|3|Mariposa County|95389|
|Yosemite National Park|3|Tuolumne County|95389|
|Yosemite National Park|1|Mariposa County|95389|
|Yosemite Valley|1|Mariposa County||
|Yosemite Village|1|Mariposa County||
|You Bet|1|Nevada County||
|Youngstown|1|San Joaquin County||
|Yountville|1|Napa County|94599|
|Yreka|1|Siskiyou County|96097|
|Yreka City|1|Siskiyou County|96097|
|Yuba City|1|Sutter County|95991|
|Yuba City Farm Labor Center|1|Sutter County|95991|
|South Yuba City|1|Sutter County|95991|
|Yuba Pass|1|Nevada County||
|Yuba-Sutter Area|2|Sutter County Yuba County||
|Yucaipa|1|San Bernardino County|92399|
|Yucca Grove|1|San Bernardino County||
|Yucca Inn|1|San Bernardino County||
|Yucca Valley|1|San Bernardino County|92284|
|Yurok Indian Reservation|2|Del Norte County|95546|
|Yurok Indian Reservation|2|Humboldt County|95546|

Question: how many places list no zip code in either the lower or upper zip code?
Answer: 18